For manufacturing such vehicle interior trim parts, see, e.g., WO 2013/150026, one approach can be to firstly introduce a decor element into a groove of a decor layer and subsequently to press an ultrasound sonotrode against the rear side of the decor layer, in the region of the groove and thus to incorporate an ultrasound weld seam connecting the decor element to the decor layer.
Several problems occur with certain approaches. On the one hand, the decor layer is relatively significantly weakened due to the incorporation of the ultrasound weld seam. This, with a mechanical loading of the decor layer can lead to damage occurring on this. A further problem is the fact that with vehicle interior trim parts manufactured according to methods from the state of the art, markings on the A-side occasionally occur and these originate from the incorporated ultrasound weld seam. The obtained connection between the decor element and the decor layer is moreover not reliably given with methods according to the state of the art, e.g., detachments of the decor element from the decor layer can occur.